The disclosure relates to a molecular electronic device and a method of fabricating the same, and more particularly, to a molecular electronic device for storing data using redox property of molecular and a method of fabricating the same.
A dynamic random access memory (DRAM) has been commercialized as a memory device. The DRAM includes unit cells each including one capacitor and one transistor. When a voltage is applied to a gate of the transistor or each unit cell of the DRAM, a channel is formed between a source terminal and a drain terminal by controlling a channel width under the gate according to the voltage applied to the gate and stored data is identified ‘1’ or ‘0’ by reading the charge state of the capacitor connected to the source terminal, in which electrons are charged or discharged according to the data.
As the memory device is highly integrated, it is difficult to secure the capacitance of the capacitor in the DRAM device and to design a structure with required capacitance.
In order to overcome such a problem, a molecular electronic device has been used as a capacitor instead of a conventional capacitor having dielectric between an upper electrode and a lower electrode.
The molecular electronic device includes an upper electrode, a lower electrode, a thin film made of self-assembled molecules over the lower electrode, and an electrolyte between the upper electrode and the lower electrode. The molecular electronic device stores electric charge using the redox property of each molecule. One molecule includes various redox potentials. The more redox potentials are included in the molecule, the more electric charges can be stored in the molecular electronic device. Therefore, it is possible to increase capacitance significantly by using the molecular electronic device, compared with a conventional capacitor. Such capacitance increment reduces the limitation of a memory device in size and structure. Accordingly, a method of fabricating a memory device using the molecular electronic device may be easier and simpler than that of fabricating a memory device using the conventional capacitor.
There is demand for developing a technology to increase capacitance more when the molecular electronic device is used as a capacitor.